碳纳米管-Mm(Ni-Co-Al-Mn)5复合储氢材料的电化学性能研究

本文首次研究了碳纳米管-MmNi_3.6Co_0.7Al_0.3Mn_0.4复合储氢材料的制备及其电化学性能,在250mA/g放电的条件下,其电化学储氢量达到320mAh/g,相同条件下MmNi_3.6Co_0.7Al_0.3Mn_0.4储氢量为270mAh/g.通过循环伏安法研究氢在复合电极上电化学特性表明,碳纳米管与MmNi_3.6Co_0.7Al_0.3Mn_0.4的复合促进了氢的吸附.     

含镓、锡的铝合金在碱性溶液中的阳极行为

铝的电极电位负,为一1．66V（VS．SHE）,电化当量高（298Ah／g）是一种理想的阳板材料．但是由于铝在空气和水中表面形成一层致密的氧化膜,使其在中性溶液中处于钝化状态．而在酸性或碱性溶液中铝表面氧化膜就会被溶解破坏,与水直接反应,腐蚀中途难以中止．这一直是影响铝作为阳板材料应用和深入研究的障碍,特别是对铝阳极活化溶解机理的研究进展缓慢．虽然目前人们在铝中添加Ga、In、11、Zn、Sn、Mg、Hg等元素,研制出各种铝合金阳极,提高了铝阳极活化性能,但是这些研究本质上仍属于经验性的．到1983年Despic等人提出了“场…     

Cryptanalysis of an ergodic chaotic encryption algorithm

In this paper, we present the results for the security and the possible attacks on a new symmetric key encryption algorithm based on the ergodicity property of a logistic map. After analysis, we use mathematical induction to prove that the algorithm can be attacked by a chosen plaintext attack successfully and give an example to show how to attack it. According to the cryptanalysis of the original algorithm, we improve the original algorithm, and make a brief cryptanalysis. Compared with the original algorithm, the improved algorithm is able to resist a chosen plaintext attack and retain a considerable number of advantages of the original algorithm such as encryption speed, sensitive dependence on the key, strong anti-attack capability, and so on.     

碳纳米管的电化学贮氢性能研究

研究了碳纳米管电极的电化学性能 ,其电化学储氢量达到 2 0 0mAh·g 1且具有高的电化学活性和良好的循环寿命 .采用循环伏安法研究了氢在碳纳米管电极上吸附 /氧化机理 .